Bug 1406505 - Improve click tests for both legacy and wdspec compliant clicks. r=ato, a=test-only
Some of the tests do not check if the click() was successful. To prove that
the click methods work, such a check always has to happen.
Also some tests should be executed in both the legacy and webdriver compliant
mode to ensure there are no regressions. Affected tests have been moved around.
MozReview-Commit-ID: Lr2TMpJHLW5

Bug 1406505 - Fix element.isInView to use table cells instead of rows. r=ato, a=test-only
As long as bug 1413493 has not been fixed the <tr> nodes will not be part
of the element tree. To workaround this problem we could use the first
found cell of the given row to check for visibility.
MozReview-Commit-ID: 57nuvxYrSMg

Bug 1406505 - Fix element.getContainer() to return button as container. r=ato, a=test-only
Because as long as bug 1089326 is not fixed child nodes of <button>
are not part of the element tree. As such the button has to be returned
as container for any of those nodes.
MozReview-Commit-ID: Jq6B9Kn7VAf